Publishers
- Christophers 2
- Chronica Botanica Company 1
- Chronicle Books 7
- Chronosports 8
- Chronosports Gsn Publishing 1
- CHT Publishing 1
- Church Missionary Society 2
- Cicada Books 1
- Cirencester Newspaper Company 1
- Cirrus Associates 2
- Citroexpert 1
- Citta Di Torino 1
- City Of Birmingham 1
- City Of Birmingham Education Department 1
- City Of Salford Art Gallery And Museums 1
- City Of Worcester 1
- Claremont Books 1
- Clarendon Press 11
- Clarion Books 1
- Clarkes New Press 1
- Classic 3
- Classic Publications 5
- Clearview 1
- Cleek Railway Solutions 1
- Clement Ingleby 1
- Clifton Books 1
- Climber's Club 1
- Clwydian-Press 1
- Clymer 3
- CMG Publishing 2
- Co-operative Wholesale Society 2
- Coachbuilt Press 1
- Cobden-Sanderson 1
- Cobden-Sanderson Ltd. 1
- Coch-Y-Bonddu Books 1
- Cocorico 1
- Colin Baxter Photography Ltd. 1
- Colin Brent Books 1
- Colin Huston 1
- Colin Orchard 1
- Collection Parthenope 1
- Collet's 1
- Collier Macmillan Publishers 2
- Collins 394
- Collins and Harvill 1
- Collins Clear-Type Press 84
- Collins Colour Camera Books 1
- Collins Lions 1
- Collins Voyager 1
- Collins Willow 7
- Colmans Foods 1
- Colnaghi And Co. 1
- Colorado Railroad Museum 1
- Colour Library Books 2
- Colour Library Books Ltd. 1
- Colour Library Direct 2
- Colourbox Publishing 1
- Colourpoint 1
- Columbia University Press 5
- Comma International Biological Systems 1
- Commission Of Conservation Canada 1
- Commonwealth Agricultural Bureaux 1
- Commonwealth Scientific And Industrial Research Organization 1
- Commonwealth War Graves Commission 2
- Compaid Graphics 2
- Company Of Stationers 1
- Compassverlag 1
- Comstock Publishing Associates 1
- Comstock Publishing Company Inc. 1
- Comyns (Publishers) Ltd. 1
- Concept Associates Ltd. 1
- Connaissance Du Rail 4
- Consejo Superior De Investigaciones Cintificas 1
- Conservation Press 1
- Consiglio Nazionale Delle Ricerche 1
- Constable 9
- Constable & Co. Ltd. 19
- Constable and Company Ltd. 20
- Constable Young Books 3
- Constable Young Books Ltd. 1
- Continuum 2
- Conway Maritime Press 14
- Copernicus 1
- Coppenrath 1
- Copple House Books 1
- Cordillera Publishing Company 1
- Corgi 1
- Corgi Avon Books 1
- Corgi Yearling Books 1
- Cork University Press 1
- Cornell University Press 4
- Cornish Brothers Limited 4
- Cornmarket 1
- Cornstalk Publishing 1
- Cornstalk Publishing Company 1
- Cornwall Books 1
- Cosmopolitan Book Corporation 1
- Costello 1
- Cote D'Or 1
- Coterie Press Limited 6